connector: add portid to unicast in addition to broadcasting

This allows replying only to the requestor portid while still
supporting broadcasting.  Pass 0 to portid for the previous behavior.

Signed-off-by: David Fries <David@Fries.net>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 22 insertions, 16 deletions

diff --git a/drivers/connector/cn_proc.c b/drivers/connector/cn_proc.c
index 18c5b9b..148d707 100644
--- a/drivers/connector/cn_proc.c
+++ b/drivers/connector/cn_proc.c
@@ -95,7 +95,7 @@ void proc_fork_connector(struct task_struct *task)
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
 	/*  If cn_netlink_send() failed, the data is not sent */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_exec_connector(struct task_struct *task)
@@ -122,7 +122,7 @@ void proc_exec_connector(struct task_struct *task)
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_id_connector(struct task_struct *task, int which_id)
@@ -163,7 +163,7 @@ void proc_id_connector(struct task_struct *task, int which_id)
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_sid_connector(struct task_struct *task)
@@ -190,7 +190,7 @@ void proc_sid_connector(struct task_struct *task)
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
@@ -225,7 +225,7 @@ void proc_ptrace_connector(struct task_struct *task, int ptrace_id)
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_comm_connector(struct task_struct *task)
@@ -253,7 +253,7 @@ void proc_comm_connector(struct task_struct *task)
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_coredump_connector(struct task_struct *task)
@@ -280,7 +280,7 @@ void proc_coredump_connector(struct task_struct *task)
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 void proc_exit_connector(struct task_struct *task)
@@ -309,7 +309,7 @@ void proc_exit_connector(struct task_struct *task)
 	msg->ack = 0; /* not used */
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 /*
@@ -343,7 +343,7 @@ static void cn_proc_ack(int err, int rcvd_seq, int rcvd_ack)
 	msg->ack = rcvd_ack + 1;
 	msg->len = sizeof(*ev);
 	msg->flags = 0; /* not used */
-	cn_netlink_send(msg, CN_IDX_PROC, GFP_KERNEL);
+	cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_KERNEL);
 }
 
 /**
diff --git a/drivers/connector/connector.c b/drivers/connector/connector.c
index a36749f..77afe74 100644
--- a/drivers/connector/connector.c
+++ b/drivers/connector/connector.c
@@ -50,7 +50,7 @@ static int cn_already_initialized;
  *
  * Sequence number is incremented with each message to be sent.
  *
- * If we expect reply to our message then the sequence number in
+ * If we expect a reply to our message then the sequence number in
  * received message MUST be the same as in original message, and
  * acknowledge number MUST be the same + 1.
  *
@@ -62,8 +62,11 @@ static int cn_already_initialized;
  * the acknowledgement number in the original message + 1, then it is
  * a new message.
  *
+ * The message is sent to, the portid if given, the group if given, both if
+ * both, or if both are zero then the group is looked up and sent there.
  */
-int cn_netlink_send(struct cn_msg *msg, u32 __group, gfp_t gfp_mask)
+int cn_netlink_send(struct cn_msg *msg, u32 portid, u32 __group,
+	gfp_t gfp_mask)
 {
 	struct cn_callback_entry *__cbq;
 	unsigned int size;
@@ -74,7 +77,9 @@ int cn_netlink_send(struct cn_msg *msg, u32 __group, gfp_t gfp_mask)
 	u32 group = 0;
 	int found = 0;
 
-	if (!__group) {
+	if (portid || __group) {
+		group = __group;
+	} else {
 		spin_lock_bh(&dev->cbdev->queue_lock);
 		list_for_each_entry(__cbq, &dev->cbdev->queue_list,
 				    callback_entry) {
@@ -88,11 +93,9 @@ int cn_netlink_send(struct cn_msg *msg, u32 __group, gfp_t gfp_mask)
 
 		if (!found)
 			return -ENODEV;
-	} else {
-		group = __group;
 	}
 
-	if (!netlink_has_listeners(dev->nls, group))
+	if (!portid && !netlink_has_listeners(dev->nls, group))
 		return -ESRCH;
 
 	size = sizeof(*msg) + msg->len;
@@ -113,7 +116,10 @@ int cn_netlink_send(struct cn_msg *msg, u32 __group, gfp_t gfp_mask)
 
 	NETLINK_CB(skb).dst_group = group;
 
-	return netlink_broadcast(dev->nls, skb, 0, group, gfp_mask);
+	if (group)
+		return netlink_broadcast(dev->nls, skb, portid, group,
+					 gfp_mask);
+	return netlink_unicast(dev->nls, skb, portid, !(gfp_mask&__GFP_WAIT));
 }
 EXPORT_SYMBOL_GPL(cn_netlink_send);